1. Field of the Invention
The present invention relates generally to temporary support means for a workpiece while the workpiece is being permanently mounted to a body, and more particularly to an improved support pin which permits a mechanic to mount a workpiece temporarily in order to free both hands for inserting the permanent mounting screws for the workpiece. One specific application of the pin is in the temporary mounting of a vehicle oil pan.
2. Brief Description of the Prior Art
A number of specialized resilient fastening and support devices have been developed over the years to simplify the installation or connection of various workpieces. These devices typically include resilient means which permit the fastening or support device to be inserted into a workpiece or into the body to which the workpiece is to be attached. The device is usually deformed in some manner while the insertion is performed, and after insertion the device recovers it initial configuration. This return to the initial configuration enables the workpiece to be fastened or supported.
For example, Kraus (L.S. Pat. No. 4,787,795) teaches a bolt-shaped push in fastener with resilient arms. As the fastener is inserted the arms are compressed, which allows the fastener to pass through an aperture. The arms have notches to engage the workpiece opening upon insertion of the fastener. Meyer (U.S. Pat. No. 3,775,927) discloses a similar selfretaining fastener. Nieuwveld (U.S. Pat. No. 3,905,570) shows a fastening device having an article-retaining head portion and a plurality of parallel resilient legs projecting from the head. The legs have a series of protrusions which grip the aperture into which the legs are inserted. Fiddler (U.S. Pat. No. 3,752,032) and Fisher (U.S. Pat. No. 3,574,899) both teach fasteners which may be fixed in an aperture, with a screw mounted within the fastener. Fegen (U.S. Pat. No. 3,777,052) discloses a support for detachably securing a circuit board to a chassis. The support device features resilient arms which may be deformed as they are pushed through an aperture, whereupon the arms regain their shapes and grip the workpiece.
Oil pan support pins are known in the prior art. These support pins simplify the installation of oil pans on automobiles, trucks, and industrial equipment. The support pins are used to support an oil pan temporarily while it is being replaced after engine maintenance or repair. The support pins known in the prior art consist of cylindrical metal pins that are threaded at one end and have a slot for a screwdriver at the opposite end. A single arm of spring steel is attached to the pin toward the end of the pin having the slot. The arm protrudes at an angle away from the support pin. After several support pins are inserted into the screw holes in the engine block which normally hold the cap screws that secure the oil pan to the block, the oil pan with gasket on top may be pushed up over the support pins and protruding arms. The protruding arm on each pin depresses easily as the pan passes over, then springs back into its normal extended position. The oil pan is now held in place below the block, and the mechanic has both hands free to install the securing cap screws and lock washers. Typical engines use between twelve and twenty of these cap screws. After the cap screws are inserted into the screw holes not occupied by support pins, the mechanic unscrews the support pins and replaces them with the remaining cap screws and lock washers.
The prior art oil pan support pins have several disadvantages. Since the pins are threaded for either English or metric threads, a mechanic must have different pins to use on vehicles having each type of thread. The prior art support pins must be inserted by threading them into place; often this requires use of a screwdriver because the threads on the engine block are not clean enough to permit hand-threading. Moreover, the prior art support pins are cylindrical. Thus, when the pins become oily (a common occurrence when oil pans are removed and replaced), the pins are difficult to grip and turn by hand. In addition, the prior art pins use only one protrusion each to support the oil pan. This increases the likelihood of failure of a pin with the result that the oil pan is not securely held in place. The prior art pins are also made of metal. Thus, their manufacture requires significant and costly machining.